Subjective well-being refers to a person's evaluation of their life (Diener, 1984). Understanding how and why culture affects well-being is essential to providing quality mental health care to all who need it (US Department of Health and Human Services, 2001 ). Recent theoretical (Markus & Kitayama, 1991 ) and empirical (Diener & Diener, 1995) analyses call into question the universal significance of internal factors such as self-esteem for determining subjective well-being. While internal factors are strong predictors of well-being in individualistic cultures such as the United States, they are less predictive of well-being in collective cultures such as Japan (Diener & Diener, 1995). Further, in collective cultures, external factors such as social appraisal (Suh, 2000) are just as important as internal factors for predicting well-being. Two studies are proposed to chart the social psychological process by which cultural differences in individualism and collectivism shape subjective experiences of well-being. Study 1 is designed to identify predictors of well-being for four major US ethnic groups (African Americans, Asian Americans, Hispanics, and European Americans) known to differ in individualism and collectivism (Oyserman, Coon, and Kemmelmeier, 2002). Self-reports of self-focused attitudes (e.g., uniqueness, alienation), social-focused attitudes (e.g., duty to ingroup, social pressure), and subjective well-being will be obtained. The relationship between self-focused attitudes and well-being is predicted to be strongest for ethnic groups high in individualsim (e.g., African Americans). In contrast, the relationship between social-focus attitudes and well-being is predicted to be strongest for ethnic groups high in collectivism (e.g., Asian Americans, Hispanics). A second goal of Study 1 is to test a theoretical model of the relationship between cultural individualism-collectivism, self-construal, and well-being (Kwan, Bond, & Singelis, 1997; Suh, 2000). It is predicted that differences in the self-concept, i.e., whether one's self-view is primarily independent or interdependent, mediates the relationship between culture and well-being. Study 2 is designed as a follow to Study 1. The primary goal of Study 2 is to identify the nature and direction of causal relationships among key variables. Experimental manipulation will be used to test for cause-effect relations. A critical element of this study is that a priori assumptions about causal relations will not be made. Instead, the direction of causal effects will be allowed to emerge from the data itself.